u/DelinquentRacoon

I was thinking and stumbled across the (possibly true?) idea that "slope" did not exist as a mathematical concept until Cartesian coordinates and graphing came into being. Which makes me wonder: what were people doing with algebra before the 1600s? or 1500s? I know advances were being made, but very little about what I'm finding talks about any practical applications.

If anyone can point to a history of math book that might cover this, I'd love a suggestion. But also, if anyone knows, I'd love a brief answer.

Thanks